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2. American Dental Association: “Expanded Functions for Dental Assistants.” Available at http://www.aapd.org/assets/1/7/StateLawsonDAs.pdf (accessed April 12, 2016).
3. Bureau of Labor Statistics (BLS): “Household Data Annual Averages-employed Persons by Detailed Occupation.” Available at: http://www.bls.gov/cps/cpsaat11b.pdf. (accessed May 23, 2016).